The present invention relates to an apparatus for providing material processing, including finishing, of an article through high speed and high energy centrifugal and rotational motion.
There has been a tremendous appreciation in recent years for the benefits and importance of surface finishing of a manufactured product. For many products it is desirable, and in some cases necessary, that the products be finished so as to have a smooth surface, without any reduction in the material characteristics of the product which may be essential for product""s intended purpose.
Various processes have been developed over the years to provide such surface finishing. Some finishing machinery use the centrifugal force imparted by a rotating vessel to finish products. A number of these machines subject objects to both centrifugal and rotational forces using a complex gearing arrangement. These types of machines are limited to a particular ratio of revolutional speed to rotational speed. Also, the construction of these existing machines is complicated requiring many moving parts, and are generally extremely noisy. Other types of machines create centrifugal forces by revolving a vessel around a shaft and creating rotational forces using a belt wrapped around the shaft and the exterior of the vessel. The speed of the belt is related to the speed of the shaft. Overheating is common in these types of machines.
One successful machine using both centrifugal and rotational forces in a simple design, without a system of gears and which can be operated at very high speeds, is disclosed in U.S. Pat. No. 5,355,638 to Hoffman, the disclosure of which is hereby incorporated by reference in its entirety. As disclosed in that ""638 patent, the centrifugal vertical finisher (or polisher) has an outer vessel that is rotatable, and at least one inner vessel that is revolved about the axis of the rotatable outer vessel and rotated about its own axis. A traction surface exists between the inner surface of the outer vessel and the outer surface of the inner vessel. The traction surface allows the outer vessel to restrain the inner vessel while the inner vessel experiences centrifugal forces. This machine simultaneously uses the momentum caused by the speed and potentially direction differential between the outer and inner vessels to produce revolution of the inner vessel.
The ""638 patent also discloses an apparatus where a center drive can be used for rotating the outer vessel and the inner vessel.
Another successful machine using both centrifugal and rotational forces is disclosed in U.S. Pat. No. 5,848,929 to Hoffman, the disclosure of which is hereby incorporated by reference in its entirety. The ""929 patent discloses a centrifugal vertical finisher with a fixed outer vessel that permits much larger objects to be finished without the need to apply excessive energy and force to the unit. Additionally, the device in the ""929 patent permits the inner vessel to be removed so that vessels of various diameters can be used in the unit without necessarily having to change the outer vessel.
While the finishing machines shown in the ""638 and ""929 patents were a tremendous advance over the then existing machines, they were limited in that products to be finished must be loaded and unloaded vertically. Thus, the configuration limits the size and number of products to be processed at a time. Also, because of the vertical orientation of the containers, some finished products tend to migrate toward the bottom of the container after finishing, requiring the container to be emptied by dumping out the contents. Furthermore, gravitational and centrifugal forces urge the media to tend to disperse in a less than isotropic manner.
A need, therefore, exists for an improved high speed centrifugal finisher which permits easy access to the contents within the finishing containers.
A horizontal centrifugal finisher is disclosed for subjecting a product to centrifugal and rotational motion. The finisher includes a main frame which rotationally supports a central shaft. The central shaft having a horizontal longitudinal axis about which it rotates. At least two radial supports are mounted to and extend radially outward from the shaft.
One or more containers are rotatably supported by the radial supports. Each container has two side walls, two end walls, a bottom and an open top. The combination of the walls and the bottom define an enclosure for containing products to be finished. A cover is attached to the container for closing off the open top. The container includes rods extending laterally outward from each end wall. The rods extend into and are supported by bearings in the radial arms. The bearings permit each container to rotate about its rotational axis.
A drive system is incorporated into the finisher for rotating the containers. The drive system includes a motor and a primary drive system. The primary drive system connects the motor to the central shaft, and is adapted to rotate the shaft about its horizontal axis, thereby causing the containers to rotate about the horizontal axis. A secondary drive system connects the motor to the containers, and is adapted to rotate the containers about their respective longitudinal axis.
In one embodiment of the invention, the secondary drive system is connected to the motor through the central shaft and is connected to the containers through an outer housing having a cylindrical inner surface. The containers include a follower mounted to each container which contacts and rolls along the cylindrical inner surface. The rolling along on the cylindrical inner surface causing the container to rotate about its longitudinal axis.
The housing is preferably a cylindrical ring which is supported by a frame. In one embodiment of the invention, there are two cylindrical rings, one on each side of the container.
In another embodiment of the invention, the secondary drive system includes a set of timing gears which are engage with the central shaft and which rotate the containers at a speed relative to the speed of the central shaft.
The foregoing and other features of the invention and advantages of the present invention will become more apparent in light of the following detailed description of the preferred embodiments, as illustrated in the accompanying figures. As will be realized, the invention is capable of modifications in various respects, all without departing from the invention. Accordingly, the drawings and the description are to be regarded as illustrative in nature, and not as restrictive.